by Andromeda » Sat Feb 23, 2013 2:37 pm
To some degree whether or not one clip causes permanent damage depends on the bird.
My GCC (who is a rehome) was not allowed to fly until he was 3 1/2 but he is an extremely good flier. He does not have noticeable damage from being clipped. I live in a two-story house and he follows me around, flying, all over the house. He can turn a complete 180 on a dime and sometimes he will fly from the living room downstairs up the stairs and into the den (or vice versa) all in one flight which not only is a good distance but requires flying up or down as well as two really tight 180 degree turns. It's hard to imagine that he could be a better flier than he is because he is excellent at maneuvering but in reality if he were always flighted he'd be even better.
However, I have another bird (a rescued brown-headed parrot) who has suffered permanent damage from being clipped, both psychologically and in regards to his ability to fly. He had a severe clip when we adopted him and had no ability to slow himself when he fell, so he would fall hard and he was a terrified bird who fell constantly. He was also in the middle of a molt and he would constantly break blood feathers (his primaries). When we went to go visit him in the rescue as soon as we entered the room (before we even had a chance to approach him) he fell and broke a blood feather just from seeing us walk through the door.
We let his wings grow out and I have been actively trying to re-fledge him for over a year but he doesn't want to co-operate; he is just not motivated to fly even extremely short distances despite being on food management. He doesn't have the confidence. He has had the ability to fly for 3 1/2 - 4 years now but the only time he flies is when he's startled. Over the course of several years of just flying face-first straight into walls, doors, cabinets and furniture he has gained a bit of control and he can slow himself down before landing and generally does not fly into obstacles anymore. Sometimes he does a few loops of the room before he lands.
He plucked for a little while and I think it was psychological and had roots in all those falls he had when he was younger combined with the fact that he feels powerless over his environment due to his inability to fly to get where he wants to go. His fearfulness is radically better than when he adopted him but he is still a cautious, somewhat fearful bird with a very strong "bite" instinct and his entire personality seems to be shaped by the clip(s) he had before we adopted him.
If you have any control over the situation do not permit your bird to be clipped.